Pass modal & trigger mail to email template

Steven Heffner  I tried like above blogs example but _controller(ITemplatablePluginController _controller) will be null and when I am checking RenderTokenString() method, I got below exception

Can you check the above code sample why _controller will be null and Can I miss any code to full _controller. Full sample code below for creating template.

using System;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.Text;
using Telligent.Evolution.Extensibility;
using Telligent.Evolution.Extensibility.Api.Version1;
using Telligent.Evolution.Extensibility.Content.Version1;
using Telligent.Evolution.Extensibility.Email.Version1;
using Telligent.Evolution.Extensibility.Templating.Version1;
using Telligent.Evolution.Extensibility.UI.Version1;
using Telligent.Evolution.Extensibility.Version1;

namespace Telligent.Test.Widget.Extension
{
    public class TestContentType : IContentType, ITranslatablePlugin, IViewableContentType, ITemplatablePlugin, IEmailTemplatePreviewPlugin
    {
       private ITemplatablePluginController _controller;
       
          public void SetController(ITemplatablePluginController controller)
        {
            controller = _controller;
        }
	   
	   private TokenizedTemplate[] _defaultTemplates;
        public TokenizedTemplate[] DefaultTemplates
        {
            get
            {
                if (_defaultTemplates == null)
                {
                    var myTemplateBody = new TokenizedTemplate("body")
                    {
                        Name = "Email - Body",
                        Description = "Body of the email.",
                        ContextualDataTypeIds = new[]
                        {
                            ContentTypes.DataTypeId
                        }
                    };
                    var myTemplateHeader = new TokenizedTemplate("header")
                    {
                        Name = "Email - Header",
                        Description = "Header of the email",
                        ContextualDataTypeIds = new[]
                        {
                            ContentTypes.DataTypeId
                        }
                    };
                    var myTemplateFooter = new TokenizedTemplate("footer")
                    {
                        Name = "Email - Footer",
                        Description = "Footer of the email.",
                        ContextualDataTypeIds = new[]
                        {
                            ContentTypes.DataTypeId
                        }
                    };
                    var myTemplateSubject = new TokenizedTemplate("subject")
                    {
                        Name = "Email - Subject",
                        Description = "Subject of the email.",
                        ContextualDataTypeIds = new[]
                        {
                            ContentTypes.DataTypeId
                        }
                    };
                    myTemplateBody.Set("en-us", @"");
                    myTemplateHeader.Set("en-us", @"");
                    myTemplateHeader.Set("en-us", @"");
                    myTemplateSubject.Set("en-us", @"");

                    _defaultTemplates = new[] { myTemplateHeader, myTemplateSubject,myTemplateBody, myTemplateFooter };
                }
                return _defaultTemplates;
            }
        }
		
		    public string GetTemplateName(EmailTarget target)
        {
            return GetTemplateNameDetails(target);
        }

        string GetTemplateNameDetails(EmailTarget target)
        {
            switch (target)
            {
                case EmailTarget.Subject:
                    return "subject";
                case EmailTarget.Header:
                    return "header";
                case EmailTarget.Footer:
                    return "footer";
                case EmailTarget.Body:
                    return "body";
            }

            return string.Empty;
        }
		
		 public void SendEmail(Guid rewardId)
        {
            CouponItems post = PointsCouponData.GetCouponDetails(rewardId.ToString());

            var context = new TemplateContext { PostTarget = "Test Redeemption" };
            context.AddItem(ContentTypes.ContentTypeId, post);

            string renderedSubject = _controller.RenderTokenString("subject", context);
            string renderedBody = _controller.RenderTokenString("body", context);

            Apis.Get<ISendEmail>().Send(new SendEmailOptions
            {
                Subject = renderedSubject,
                Body = renderedBody,
                ToEmail = "test1@gmail.com"
            });
        }
		
		}
		
		}

Please check the above samples and help me If I miss any interface or code, thanks!

SetController has the assignment backward, you need to assign your local _controller = controller, the passed in controller reference.